Wellington Guelph Dufferin Public Health is reporting four overdose deaths since late February, including one in the Arthur area and one in the Elora area.
In each case, public health officials believe Fentanyl was involved, with red and purple-coloured Fentanyl involved in two of the deaths.
Officials add any coloured substance may pose a risk.
And with the reports, public health warns it is a suggestion that a stronger than normal substance is circulating in communities.
The other two overdose cases reported were in Guelph and Rockwood.
